Ive obtained some ALUM powder which seems to give a result very similar to baking soda. but at a bit higher voltage. and a bit more capacity.
PH is about 3-3.5 so a bit acidic but not by much. more performance.

 

I used TEN layers of napkins and this time I wrapped it as tightly as I could by hand. which seems to be working extremely well so far! The surface charge effect is huge. like that of a much larger battery.
it holds charge for a very long time!

 

I'm not sure but I think my alum sulfate powder is slowly being consumed somehow in the charging/discharging process as I cycle my battery?

I have a little excess that wouldn't dissolve at the bottom of my container.
However after several hours and a couple dozen cycles its slowly decreasing and now almost gone.
Where is it going?

 

Well ALUM didn't really work too well.
Gave up on alum and just switched to using plain and simple baking soda. Works WAY better. I dont know why but baking soda is really powerful and works very good.

 

This is what I have so far.
Images
https://cdn.discordapp.com/attachme...3/1151764969285746729/IMG_20230914_015055.jpg
https://cdn.discordapp.com/attachme...3/1151764969742938152/IMG_20230914_015159.jpg
https://cdn.discordapp.com/attachme...3/1151764970028138597/IMG_20230914_015139.jpg

 

I'm not sure why but it seems to have a preference for more capacity one way than the other. even though the spiral should be basically identical.

Is my spiral incorrect? Do I need to "twist" it from the middle instead of from one end?

 

I scrounged up a very old 6v 5AH AGM lantern-top style battery out of the closet
charged it up fully
and discovered a very weird behavior on discharging.

Discharged to 5.25v at 1.4A gave about 3007mAh
Then lowered the current to 0.5A and discharged to 5.25v gave an additional 532mAh on top of the 3007mAh

Lowered it again to 0.3A to 5.25v and it gave about 253mAh on top of that

Now with the current lowered to 100mA it started just steadily climbing in voltage up to 5.56v and stayed there for well over an hour. not budging or flinching. just STAYING at 5.56v the entire time.
Currently about 127mAh additional discharged and still increasing.
the battery is from about 2015-2016 and quite abused. sitting with no charge for years at a time. barely being topped up at all.
I have no idea how long it will stay at 5.56v because it hasn't changed in the past hour and a half.

 

Was looking promising for a while and the voltage suddenly went open circuit (immediate drop to close to 0v). it dropped a cell interconnection!

Took it apart wearing gloves. neutralized all the acid with heaps of baking soda
Discovered all the positive electrodes are just muishy wet goo. Disintegrating like fine sand.

However there was no visible sulfate buildup on either electrode. None at all. Spotless even.

And the negative electrodes all look almost as good as brand new. Still good solid lead thats very usable.

I decided to try taking a pair of very good looking negative electrodes and repurposing them into a "new" battery as a test to see if my idea would work.

And it did! I'm able to charge up the negative electrodes using one as a positive and two as the negative and it begins forming a new lead dioxide layer into the cell and charging up!

Tried various electrolytes and the best performer seems to be epsom salt or baking soda. Haven't really decided which is the best
but baking soda seems to be the most promising
Epsom salt seems to have some kind of issue causing instability. Something to do with the electrolyte interacting with the surface of one of the electrodes in some way. Not sure.

Alum is useless and doesn't perform at all. Total disappointment.

 

I'm even more confused now.
it is behaving exactly how a lead acid battery works now.
Open circuit voltage is exactly matching that of a sealed lead acid battery. Right on the money. 2.11-2.15 per cell open circuit.

And it functions like one thats brand new. though of somewhat reduced capacity due to fewer plates

 

is it possible since the battery was fully discharged. during charging some of the sulfuric acid came out of the lead sulfate within the plate. protected from being neutralized. and created new sulfuric acid somehow?
Even though the epsom salt should be the main electrolyte and the voltage should be roughly between 1.8-1.9v open circuit.
it actually holds much higher than that after applying a load and letting the voltage rebound. it rebounds to over 2v after 60mAh has been extracted at over 1 amp of discharge current.

 

Even more experiments.
Turns out using zinc as the negative electrode improves things even more.
I made a really small test setup and the open circuit voltage is like 2.4v+ fully charged. with the positive electrode being lead dioxide layer and the negative being a lead or zinc electrode with a zinc powder paste covering its surface.

 

I made a really simple and crude "pasted electrode" test cell using just a piece of soldering wire with one end formed into a small circle. then I took some lead turned it into a granular form and turned that into a wet paste with baking soda and water mixed in to it.

Then put that into the circle of the soldering wire ends and sandwiched them together using a bunch of layers of coffee filter paper as the separator as well as on the sides. with some sturdy plastic pieces and zipties to hold it all together tightly. making somewhat of a coin-like battery cell.

Then started charging it and testing it.

It seems to work however from what i'm seeing only the surface layer of the electrode pastes seems to be changing into the oxide form. and the interior/main body of it is mostly staying in metallic form.

Does it just take an extremely long time for the oxide layer to form deeper into the electrode paste surfaces?
I got about 2mAh out of a cell the size of my thumbnail but I was expecting closer to 20-50mAh

it is about 1.6mm thick granular pasted electrodes. about 0.75 inches across.

 

Removed "formed" cells from the sandwich setup and replaced the electrolyte with a bath of roughly 50% saturation epsom salt mixture as well as a very small pinch of just a few granules of alum powder

something VERY interesting has started happening
PH at the start was neutral. ph strips did not change color.

but after just one charge and discharge cycle the ph has dropped from neutral to about a 4

And it seems to be still dropping further from 4. very slowly and gradually.

The resting voltage of the battery becomes higher and higher. it is almost resting at the voltage of a freshly fully charged lead-acid cell.

How can the PH be dropping so much?

 

ok the absolute BEST performing result ive gotten so far is the zinc from a penny as the negative. and a pure lead positive electrode.
Using alum for the electrolyte as I dont have anything more suitable right now.
I get sustained voltage of just about 2v under a small load until the positive electrode has completely ran out of energy. Very flat discharge curve until its about empty.
4mA continuous for a similar size piece of lead as a zinc penny for about 15+ minutes with about 1.7-2v open circuit in a very crude and simple cell setup. not even sandwiched together.
Sandwiched together I'm guessing the voltage would be even higher under load. along with some suppression of gas generation by the separator.
The negative electrode tends to gas almost continuously while charging or discharging.
but the positive electrode simply changes color slightly. from fully charged to fully discharged.

The negative zinc electrode seems to hold a lot more capacity and power than the lead positive electrode. Even after discharging to 0v checking the half-cell potential with my multimeter and a dummy piece of solder wire with no charge on it. i get about 0.56v on the zinc. with a small negative voltage on the positive electrode of just about -0.020mv

So the positive runs out far sooner than the negative electrode.
How could I get the positive to store more energy to more symmetrically match up with the negative electrode? So I get a more even discharge between the different materials?
It does seem to be rechargeable fine no dendrites on the zinc.
but the zinc took a LONG LONG time to charge up the first time. Like 100 times longer than the lead positive electrode.
Almost all day for the zinc to come up to a positive voltage of about 0.6-0.7v

Open circuit resting voltage is between 2.1-2.4v so pretty good! Maybe even a little better than a lead acid battery

Does not get damaged when discharged deeply.

 

On further experimentation. it seems sodium carbonate is a powerful choice for capacity. overcharging/corrosion resistance. power. and overdischarge resistance.

Downside is lower voltage potential range. and possibly more risk of injury if you come into contact with the electrolyte.

No clue what possible/suitable additives could be. as I dont have anything that would be compatible with the sodium carbonate.

it has been going an incredibly long time holding steady at 2.5mA of discharge current for over an hour. while maintaining close to 1.1-1.2v
it is coming up on an hour and 15 minutes and not showing any signss of dropping off.
Only a couple thin 0.3mm strips of lead foil dipped into a small container of electrolyte. spaced apart about 1.25" apart. and their length is approximately 2.75 inches long. and width across is 0.6 inches
the surfaces facing each other have been roughened up with some 220 grit to remove any debris or factory greases or solvents. and give more surface area.
The surfaces not facing each other have been simply wiped repeatedly with tissue until clean.

edit even able to sustain 30mA for about 11 minutes before the voltage even starts dropping off from 1v! almost 8mAh with just these small pieces of foil.

 

Hmm... It's working ok. but the self-discharge rate is still abnormal.
I even tried charging the electrodes fully. then immediately removing them and putting them into a container of deionized plain pure water (no electrolyte solution). Rinsed them off in it. then put them in another container of deionized plain pure water.

Let them sit for a few hours. and the voltage still dropped as if the electrodes themselves are discharging themselves!
How are the electrodes self-discharging themselves?

The negative electrode shows almost no appreciable self-discharging.
but the positive electrode slowly loses a charge (approaches 0v half cell potential relative to the negative electrode) over time.
I'm not sure what i could be missing?

 

I got it to run a 2.5mA load for about 2 hours before it dropped under 1v!
With a higher current discharge rate. about 30mA I get about 17 minutes of runtime before the voltage starts dropping off. below about 1v again. so a little over 12mAh! without even having the advantage of pasted or particle battery plate.

 

Very strangely a cloudy precipitate is created if you apply a voltage and small current to lead electrodes in a very dilute baking soda and distilled water solution
but beyond a certain point as you add more baking soda to the solution and it becomes more saturated. it stops producing a cloudy precipitate. and just changes the electrodes between metalic lead and a lead oxide form

I wonder what the cloudy precipitate is? it appears to be some sort of insoluble compound. but what?

 

seems like making a combined near saturated solution of both sodium sulfate and sodium carbonate with a bit of borax also added seems to give the highest possible output current. when testing a small cell in a jar/cup

Almost super-capacitor-like performance. Put the electrodes very close together with a singular sheet of paper towel or something. pressed flat. and you get several amps out of a very small surface area. for a few seconds.

Edit: Apparently adding baking soda even MORE further enhances the power and capacity of the battery.
Not sure if theres a specific ratio I should aim for. but having a mixture of all 4 things keeps the voltage the highest under load and outputs the highest current.

 

I just tried something else now.
Just baking soda and sodium sulfate.
LITERALLY insane result.
0.62 amps of current with the tiny strips of foil separated by 1.5 inches approximately distance apart.
About 2.8 inches of electrode material length in the liquid.
Thickness is about 0.3mm. with the surface textured by hammering with 400 grit and 300 grit sandpaper to roughen them up without creating a lot of dust or losing mass/material.
about 0.55 inches width across.


it peaked around 0.62 amps then gradually decreased to about 0.4 amps after a few seconds. then slowly declined to about 0.2A from there.
Suddenly dropping off after it reached around 0.16A of current. after about 10 seconds

The negative electrode bubbled so vigorously during the first few seconds of discharge that some liquid even escaped the container as a vapor!